KUALA LUMPUR (Reuters) -- Malaysia's prime minister is expected to reshuffle his Cabinet soon, but there are few signs of radical changes to a line-up where some ministers joined the Cabinet before half the population was born.

Abdullah Ahmad Badawi's information minister gave him the chance for a reshuffle on Tuesday when he said he was resigning from the Cabinet after almost 35 years in government office.

Malaysia's main dailies all carried front-page stories saying Abdullah would use the new vacancy to drop some other ministers and bring some new faces into the cabinet, and that the reshuffle could be announced this week. Information Minister Abdul Kadir Sheikh Fadzir said he was resigning his post to spend more time with his family and added: "I don't know when there will be an announcement of a cabinet reshuffle, but I will stay on until the reshuffle."

A source close to government said not to expect a dramatic overhaul. "My sense is that it won't be so much of the big names being dropped," the source told Reuters.

Abdullah Ahmad Badawi, 66, gained the leadership in late 2003 from his old boss, Mahathir Mohamad, 80, who dominated Malaysian politics during his 22 years in power and whose ministers largely outlasted him and continued in office.

Two ministers, including Trade Minister Rafidah Aziz, have been in Cabinet for more than 24 years -- before roughly half of Malaysians were born, according to 2000 data. Dubbed the "Iron Lady" of local politics, Rafidah is reputedly the world's longest-serving trade minister.

Since Abdullah came to power, he has been criticized for not putting a broom through Cabinet. His critics argue that his pledge to root out corruption from politics and the civil service would be helped by a rejuvenation of his Cabinet.

Reshuffle momentum building

They say Abdullah missed his first chance to shape his own Cabinet in 2004, when he made only a minor reshuffle despite having just boosted the ruling coalition's mandate and winning a massive election victory on his anti-graft agenda.

The momentum for another reshuffle has been building since several cabinet ministers, including Kadir, lost out on key positions in the main ruling party's last internal elections in 2004. The ministers for home affairs and higher education also lost out in those polls, leaving their cabinet posts vulnerable.

Trade Minister Rafidah and another Cabinet veteran, Samy Vellu, have hit rocky patches under Abdullah's reign but the source said both were considered very able ministers. They might be shifted to other jobs rather than being dumped, he added.

Political analyst Abdul Razak Baginda said he did not expect a radical overhaul because Abdullah was constrained by internal coalition politics. He noted Rafidah was the head of her party's women's wing while Samy Vellu headed his ethnic Indian party.

"I don't think any of the top guns will be dropped," Abdul Razak said, adding that such powerful ministers could be better at driving reform in the civil service than new ministers.